GHSA-Q9PG-JJ6X-J9P6 Gitea: draft release attachment disclosure via missing web authorization

Summary Gitea's draft-release access control is enforced only on the API release endpoints /api/v1/repos/owner/repo/releases/id and its /assets/... sub-routes but not on the web-level UUID-based attachment endpoints /attachments/uuid, /owner/repo/attachments/uuid,...